Shaker apparatus



Jan. 11, 1966 E. K. STRAND 3,228,522

SHAKER APPARATUS Filed March 20, 1963 4 Sheets-Sheet 1 Fla. 1

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Jan. 11, 1966 Filed March 20, 1963 E. K. STRAND SHAKER APPARATUS BUUBHW 4 Sheets-Sheet 2 F/(iZ IN VENTOR. Em me A. JTRAND f/Mwtw Arramvsrr Jan. 11, 1966 E. K. STRAND 4 Sheets-Sheet 5 INVENTOR ERL/NG A. STRAND W WQQJ ATTORNEYJ Jan. 11, 1966 E. K. STRAND SHAKER APPARATUS 4 Sheets-Sheet 4 Filed March 20, 1963 0 RN ma mm Mm m L R 5 BY qzgmxw Arron/vers- United States Patent 3,228,522 SHAKER APPARATUS Erling K. Strand, 9743 Humboldt S., Bloomington, Minn. Filed Mar. 20, 1963, Ser. No. 266,592 6 Claims. (Cl. 209-343) The present invention relates to shakers for screening finely divided particulate material and more particularly to shakers of the type suited for screening grain for the purpose of sizing and sorting the same.

A variety of shakers have previously been proposed for conducting screening tests. Many of these previous shakers have not only been difficult to operate but also produce inconsistent results due to the fact that they must be ope-rated by hand. Another important shortcoming of many shakers previously proposed is that they are ineffective in halting the movement of the shaker pan after a predetermined number of oscillations. For this additional reason, it was often impossible to obtain reproducible test results. A further defect in many of the shaker mechanisms previously proposed is that they are relatively bulky, complicated in construction and can be manufactured only at a relatively high cost. Still another common defect in many shakers is that large particles tend to pack the screens thus reducing screening efiiciency.

In view of these and other defects of the prior art it is thus one object of the present invention to provide an improved shaker apparatus which is particularly well suited for screening grain and the like and which can be reliably halted after a predetermined number of oscillations.

A further object of the present invention is the provision of an improved shaker apparatus including a drive motor thereon and an improved drive assembly for imparting reciprocal movement to the shaker pan.

Yet another object of the present invention is the provision of a shaker including an improved brake assembly for rapidly and reliably halting movement of the shaker pan after completion of a predetermined number of oscillations.

Yet another object of the present invention is the provision of a shake-r for grain and the like having an improved control assembly including a switch and a switch operating member connected for movement with the drive system for opening the switch after the pan has oscillated a predetermined number of strokes.

A still further object of the present invention is the provision of an improved shaker apparatus including a drive motor, a switch for controlling the operation of the drive motor and a novel and simplified system for closing the switch when the apparatus is to be started.

A still further object of the present invention is the provision of an improved shaker including a means for imparting a rocking movement to the shaker pan when the carriage upon which the pan is mounted reverses direction for the purpose of increasing screening efficiency.

Other objects of the invention will become apparent as the description proceeds.

To the accomplishment of the foregoing and related ends, this invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principles of the invention may be employed.

The invention is illustrated by the accompanying drawings in which the same numerals refer to corresponding parts and in which:

3,228,522 Patented Jan. 11, 1966 ice FIGURE 1 is a longitudinal sectional view of a shaker embodying the present invention taken on the line 1-1 of FIGURE 3;

FIGURE 2 is a plan View of the apparatus of FIGURE 1;

FIGURE 3 is a view of the underside of the apparatus;

FIGURE 4 is a transverse vertical sectional view taken on the line 44 of FIGURE 3; and

FIGURE 5 is a partial side elevational view of the apparatus showing a modified form of carriage and screening pan.

Briefly stated the present invention provides a grain shaker including a sup-porting framework with a carriage mounted thereon for sliding movement and a drive means for imparting reciprocal movement to the carriage. According to a preferred form of my invention, a brake is operatively connected to the drive means for quickly halting the movement of the carriage upon the framework. A control means is operatively connected to the drive means for operating the brake after the carriage has reciprocated a predetermined number of times. According to a modified form of my invention, a provision is made for allowing limited sliding movement of the pan with respect to the carriage for increasing screening efficiency.

Referring now particularly to the drawings wherein the same numerals refer to corresponding parts in the several views there is shown a shaking apparatus according to a preferred form of my invention including a supporting framework 10 having side walls 12 and end walls 14 and a top wall 16. Suitably attached to the framework at its lower end are four support legs 18 each of which is vertically adjustable so as to enable the apparatus to be leveled before use. Rigidly secured to the upper wall 16 by means of bolts 19 is a drive motor 20. As best seen in FIGURE 2, the bolts 19 project through parallel longitudinally ext-ending slots 22 which enable the drive chain more fully described hereinbelow to be tightened as required.

Extending vertically from the upward end of the motor 20 is a motor drive shaft 24 upon which is secured a sprocket 26. A similar sprocket 28 is afiixed to a shaft 29 journalled for rotation about a vertical axis within a bearing 30 which is itself rigidly secured to the housing 10. Entrained over the sprockets 26 and 28 is a flexible drive means such as a sprocket chain 32. Rigidly secured to one of the links of chain 32 and extending upwardly therefrom is a drive arm 34. R-otatably mounted on the upper end of the drive arm 34 is a slide block 36. The slide block 36 projects into a transversely extending slot 38 in a carriage 40 which is itself mounted for reciprocal sliding movement upon a pair of parallel and spaced apart slide members such as rods 42 and 44. To this end the carriage 40 includes three spaced apart downwardly extending legs 45, 46 and 48 suitably bored to slide smoothly upon the rods 42 and 44. The rods 42 and 44 can be supported on the framework 10 in any suitable way as by means of mounting blocks 50.

It will thus be understood that during operation as the drive motor 29 turns the sprocket 26 and the drive chain 32 will carry the arm 34 and block .36 around the sprockets 26 and 28 and as the arm 34 moves from one sprocket to another, reciprocating movement will be imparted to the carriage 40. The block 36 will, of course, slide laterally within the slot 38 as it passes around the end of each of the sprockets 26 and 28.

Rigidly afiixed to the lower end of the shaft 29 is a brake assembly including a sheave 52 over which is wrapped a length of belt such as a section of a conventional drive belt 54. As best seen in FIGURE 3, one end of the drive belt 54 is rigidly secured to one end wall 14 by a fastener 56. The other end of the belt 54 is suitably resiliently connected to the end wall 14 by means of a spring 58. An electric motive power unit such as solenoid 60 of any suitably well known construction is secured on a supporting block 62 which is itself rigidly connected to the top wall 16 of the framework 10. The solenoid 60 also includes a conventional plunger 64 the outward end of which is connected by means of a link 66 to the end of belt 54 secured to the spring 58.

During operation, as the plunger 64 of the solenoid 60 is retracted into the solenoid, the links 66 will move toward the left as seen in FIGURE 3 thereby drawing the free end of the 'belt 54 toward the left while simultaneously elongating the spring 58. As this occurs, the tension of spring 58 which normally forces the belt 54 into engagement with the sheave 52 will be relieved so that sheave 52 will then be free to turn. On the other hand, when the plunger 64 is extended to the position shown in FIGURES 1 and 3 the spring 58 will force the free end of the belt 54 toward the right in the figures thereby pressing the belt 54 tightly into contact with the sheave 52 and in this way reliably preventing rotation of the shaft 29 and chain 32.

Rigidly mounted upon the framework below the shaft 29 is a cross member 70 upon which is mounted a bearing block 72. Extending downward from the shaft 29 and rigidly connected thereto is a smaller shaft 74 best seen in FIGURE 4. Similar shafts 76, 78 and 80 are also journalled in the bearing block 72. Mounted upon the lower end of the shafts 74, 76, 78 and 80 are mating speed reducer gears of known construction indicated generally at 82 in FIGURES 1, 3 and 4. It will be apparent from an inspection of FIGURE 4 that the gear on each of shafts 74 to 80 mates with a larger gear on the next succeeding shaft so as to accomplish a substantial speed reduction at shaft 80. Rigidly connected to the upward end of the shaft 80 is a switch engaging arm 84. At the outward end of the arm 84 is an extension in the form of a bolt having a rounded head 86..

Rigidly mounted upon the supporting framework 10, is a slide block 90 having a laterally positioned recess 92 on the lower surface thereof. Extending across the open side of the slot 92 and suitably fastened to the block 90 on either side of the slot 92 is a supporting bar 94. Slidably mounted within the slot 92 is a switch supporting bar 98 upon the lower side of which is mounted a normally closed switch 100 including a switch operating lever 101 having a wheel at its free end. Switch 100 also includes a terminal 103 and a terminal 105.

Connected to the opposite end of the bar 98 is a starting button 102. Button 102 is slidably mounted within an opening 104 in the wall 12 of the framework 10.

As best seen in FIGURES 1 and 4, a spring 106 is connected between the slide block 90 and bar 98. The spring 106 is constructed for yieldably biasing the bar 98 toward the left in FIGURE 4 so as to maintain the button 102 extended outwardly from the wall 12 of the framework 10. Thus, during the operation, when the button 102 is depressed the supporting bar 98 will move inwardly or toward the right in the figures against the force of spring 106 thereby moving the switch 100 laterally with respect to the speed reducing gears 82 and arm 84 as will be explained more fully hereinbelow.

Referring now more particularly to FIGURE 3, it will be seen that a pair of conductors 120 and 122 supply current to the motor from lead in wires 124 and 126. The solenoid 60 includes input terminals 128 and 139 which are connected in parallel with the motor 20. The operating switch 100 is connected in series with both solenoid 60 and motor 20 by means of a conductor 132 extending between terminal 103 and the terminal 128. The terminal 105 is connected to lead in wire 126.

As best shown in FIGURE 4, suitable support plates 138 (only one of which is shown) project upwardly in the upper surface of the carriage 40 for supporting the side of a screening pan 140 of any suitable known construction. While the pan 140 can be constructed in various ways it ordinarily includes an inner pan element 142 having a screen 144 at the lower end thereof. A clamping block 146 extends across the top of the pan 140 and resilient members such as springs 148 extend from the ends of the block 146 to the ends of the carriage 40 for the purpose of securely retaining the pan 140 on the carriage 40.

Operation To initiate the operation of the apparatus, the material which is to be screened is placed in the pan 140 above the screen 144 and the button 102 is pressed inwardly thereby shifting the supporting bar 98 toward the right in FIGURE 4. As the bar 98 slides laterally within the block 90, the spring 106 will, of course, be compressed. Simultaneously, the switch operating lever 101 on the switch 100 will move out of engagement with the head 86 of a switch actuating arm 84. Switch 100 will then close, creating a circuit from the lead wires 124 and 126 through the motor 20 and also through the solenoid 60. As the motor 20 operates, the carriage 40 will, of course, reciprocate upon the slide rods 42 and 44. At the same time, the plunger 64 of solenoid 60 will be retracted toward the left in FIGURE 3 thereby extending spring 58 and relieving the pressure exerted by belt 54 on the sheave 52. The shaft 29 and chain 32 will therefore be free to turn.

As the carriage 40 oscillates upon the supporting framework, the reduction gears 82 will of course rotate thereby causing the arm 84 to turn relatively slowly about the center of shaft until the head 86 again contacts the switch actuating lever 101 at which time the switch \will be opened and the current to the motor 20 and to the solenoid 60 will be interrupted. As soon as the current to the solenoid 60 is interrupted, the plunger 64 will be entended toward the right in FIGURE 3 by spring 58 thereby tightly wrapping belt 54 about the sheave 52 and thus rapidly and reliably halting the movement of the carriage 40.

When it is desired to operate the apparatus again, it is only necessary to depress the button 102 as described above thus starting the cycle of operation a second time.

Refer now particularly to FIGURE 5 which illustrates a modified form of my invention. In this form of the invention a receiver 200 is mounted upon the upper surface of the carriage 40. The receiver 200 is rigidly secured to the carriage 40 by means of suitable fasteners (not shown). The receiver 200 comprises a ring 202 extending entirely around the periphery of the carriage 40 and including a opening 204 in the center thereof to receive a screening pan 206. Other pans such as pans 208 and 210 can be mounted above the pan 206. Between each of the pans is provided a suitable screen 212 of any known construction. A hold down bar 214 is suitably mounted above the uppermost pan 210 and a pair of springs 216 and 218 extend between the bar 214 and the receiver 200.

According to the form of my invention shown in FIG- URE 5, the opening 204 in the receiver 200 is made slightly larger than the outside diameter of the pan 206 and for this reason the inside edges of the receiver 200 function as stops for allowing limited oscillatory movement of the pans 206, 208 and 210 with respect to the carriage 40. Thus, when the carriage 40 has moved all the way to the right in FIGURE 5, the pans will slide toward the right end of the opening 204 and strike against the right inside edge thereof. This will cause a mechanical shock to be imparted to the pans thereby increasing the screening efficiency of the apparatus. As the carriage 40 travels in the opposite direction to the dotted line position of FIGURE 5 and begins to reverse direction again, the pans 106 will strike the left end of the opening 204 thereby causing another shock to be imparted to the pans. Moreover, as seen in FIGURE 5, by properly adjusting the speed of movement of the carriage, the spring tension of the springs 216 and 218 and the weight of pans 206, 208 and 210, the pans can be made to tilt or rock through a small angle with respect to the vertical, so that one end of pan 106 is elevated from the face of the carriage 40 as shown at 220. This rocking action will tend to throw the grain in the pans upwardly from the screens thus further increasing the screening efficiency of the apparatus.

A number of shakers embodying the present invention have been manufactured and used under actual service conditions. They were found to be effective in operation and would reliably halt the carriage motion after the latter had reciprocated a predetermined number of strokes. Moreover, the test results obtained were more consistent than those obtained with hand operated machines. Screening efficiency was found to be improved since larger particles were prevented from packing the screen.

Numerous modifications can be made in the structure set forth. For example, a commercially available electric timing switch (not shown) can be used in place of the switch 100 in which event the timing gears 82 and arm 84 can be eliminated. When this modification is made, the cycle of operation is limited to a predetermined time interval rather than to a predetermined number of strokes of the carriage 40.

It is apparent that many modifications and variations of this invention as hereinbefore set forth may be made without departing from the spirit and scope thereof. The specific embodiments described are given by way of example only and the invention is limited only by the terms of the appended claims.

What is claimed is:

1. A grain shaker for use with a shaker pan comprising in combination a supporting framework, slide means mounted upon said framework, a carriage mounted for sliding movement upon said slide means, said carriage being adapted to support said shaker pan, a drive means, a connecting means between said carriage and said drive means for reciprocating said carriage upon said slide means responsive to the operation of said drive means, brake means operatively connected to said drive means and a control means operatively connected to said brake means for engaging said brake means to always stop said carriage in the same position relative to said frame after said carriage has reciprocated a predetermined number of times upon said slide means, said control means comprising a switch conductively connected to said drive means for turning on and off said drive means, a switch actuating element operatively connected to said connecting means for movement therewith and positioned to open said switch after said carriage has been moved through a predetermined number of cycles of said drive means, and solenoid means connected to said brake means and operative upon opening of said switch to positively actuate said brake means.

2. A grain shaker for use with a shaker pan comprising in combination a supporting framework; slide members mounted upon said framework; a carriage mounted for sliding movement upon said slide'members, said carriage being adapted to support said shaker pan; a drive motor; a connecting means between said carriage and said drive motor for reciprocating said carriage upon said slide members responsive to the operation of said drive motor; brake means operatively connected to said connecting means and a control means operatively connected to said brake means for engaging said brake means to always stop said carriage in the same position relative to said frame after said carriage has reciprocated a predetermined number of times upon said slide members; said control means comprising a switch means conductively connected to said motor for turning on and off said motor, a switch actuating element operatively connected to said connecting 6 means for movement therewith and positioned to open said switch means after said carriage has been moved through a predetermined number of cycles by said drive motor, and actuator means operative upon opening of said switch means and connected to said brake means to positively actuate said brake means.

3. A grain shaker according to claim 2 further characterized by the provision of a pan receiver mounted upon said carriage, said receiver being adapted to receive said shaker pan, said receiver being of larger diameter than said pan whereby said pan will oscillate within said receiver upon said carriage to strike against the inside of the receiver to impart a mechanical shock to said pan when said carriage is reciprocated upon said slide members.

4. A shaking apparatus for screening particulate material comprising in combination a supporting framework, a drive motor mounted upon said framework, a drive assembly operatively connected to said motor, slide means mounted on said framework, a carriage mounted for reciprocal movement on said slide means, means on said carriage for supporting a screen shaker pan, said drive assembly being operatively connected to said carriage for reciprocating said carriage upon said slide means, conducting means operatively connected to said motor for supplying current thereto, switch means conductively connected to said motor for starting and stopping said motor, a control means operatively connected to said drive assembly for regulating the operation of said switch means, said control means including a switch operating member positioned to engage said switch means after said drive assembly has moved said carriage through a predetermined number of cycles, brake means operatively connected between said framework and said drive assembly, an electrical motive power unit operatively connected to said brake for engaging and disengaging said brake and conductor means connected between said switch means and said motive power unit for operating the unit when the switch means is closed.

5. A shaking apparatus for screening particulate material comprising in combination a supporting framework, a drive motor mounted upon said framework, a drive assembly operatively connected to said motor, slide means mounted on said framework, a carriage mounted for reciprocal movement on said slide means, means on said carriage for supporting a screen shaker pan, said drive assembly being operatively connected to said carriage for reciprocating said carriage upon said slide means, conducting means operatively connected to said motor for supplying current thereto, brake means operatively connected to always positively stop said drive assembly and said carriage in the same position relative to said frame after said carriage has been reciprocated through a predetermined number of cycles, an electrical motive power unit operative with said motor and operatively connected to said brake means, switch means conductively connected to said motor for starting and stopping said motor and conductively connected to said motive power unit for regulating operation of said brake means, a control mean operatively connected to said drive assembly for regulating the operation of said switch means, said control means including a switch operating member positioned to engage said switch means after said drive assembly has moved said carriage through a predetermined number of cycles, said switch means being mounted upon said framework for movement between a first position and a second position, said switch in said second position being out of engagement with said switch engaging member and when in said first position being adapted to contact said switch engaging member whereby said switch will be actuated by movement between said first and second positions.

6. A shaker adapted to hold a pan for screening particulate material such as grain, said shaker comprising in combination a supporting framework, guide means thereon, a carriage mounted upon the guide means for reciprocal sliding movement along a horizontal path, means on said carriage for supporting a screen shaker pan, drive means mounted upon the framework and operatively connected to the carriage for imparting reciprocal sliding movement to the carriage, brake means mounted upon the shaker and operatively connected between said carriage and said framework to always positively stop said drive assembly and said carriage in the same position relative to said frame after said carriage has been reciprocated through a predetermined number of cycles, a solenoid operative with said motor and operatively connected to said brake means, switch means conductively connected to said motor for starting and stopping said motor and conductively connected to said solenoid for regulating operation of said brake means, a control means operatively connected to said drive assembly for regulating the operation of said switch means, said control means including a switch operating member positioned to engage said switch means after said drive assembly has moved said carriage through a predetermined number of cycles, said switch means being mounted upon said framework for movement between a first position and a second position, said switch in said second position being out of engagement with said switch engaging member and when in said first position being adapted to contact said switch engaging member whereby said switch will be actuated by movement between said first and second positions.

References Cited by the Examiner UNITED STATES PATENTS 1,485,946 3/ 1924 Battenfeld 209338 1,500,850 7/1924 Rush 209338 2,374,215 4/ 1945 Korenyi 7437 2,591,688 4/ 1952 Faulkner 2 09342 2,663,423 12/ 195 3 Wheeler 209-309 3,036,710 5/ 1962 AXsom 209-291 HARRY B. THORNTON, Primary Examiner.

HERBERT L. MARTIN, Examiner. 

4. A SHAKING APPARATUS FOR SCREENING PARTICULATE MATERIAL COMPRISING IN COMBINATION A SUPPORTING FRAMEWORK, A DRIVE MOTOR MOUNTED UPON SAID FRAMEWOR, A DRIVE ASSEMBLY OPERATIVELY CONNECTED TO SAID MOTOR, SLIDE MEANS MOUNTED ON SAID FRAMEWORK, A CARRIAGE MOUNTED FOR RECIPROCAL MOVEMENT ON SAID SLIDE MEANS, MEANS ON SAID CARRIAGE FOR SUPPORTING A SCREEN SHAKER PAN, SAID DRIVE ASSEMBLY BEING OPERATIVELY CONNECTED TO SAID CARRIAGE FOR RECIPROCATING SAID CARRIAGE UPON SAID SLIDE MEANS, CONDUCTING MEANS OPERATIVELY CONNECTED TO SAID MOTOR FOR SUPPLYING CURRENT THERETO, SWITCH MEANS CONDUCTIVELY CONNECTED TO SAID MOTOR STARTING AND STOPPING SAID MOTOR, A CONTROL MEANS OPERATIVELY CONNECTED TO SAID DRIVE ASSEMBLY FOR REGULATING THE OPERATION OF SAID SWITCH MEANS, SAID CONTROL MEANS INCLUDING A SWITCH OPERATING MEMBER POSITIONED TO ENGAGE SAID SWITCH AFTER SAID DRIVE ASSEMBLY HAS MOVED SAID CARRIAGE THROUGH A PREDETERMINED NUMBER OF CYCLES, BRAKE MEANS OPERATIVELY CONNECTED BETWEEN SAID FRAMEWORK AND SAID DRIVE ASSEMBLY, AN ELECTRICAL MOTIVE POWER UNIT OPERATIVELY CONNECTED TO SAID BRAKE FOR ENGAGING AND DISENGAGING SAID BRAKE AND CONDUCTOR MEANS CONNECTED BETWEEN SAID SWITCH MEANS AND SAID MOTIVE POWER UNIT FOR OPERATING THE UNIT WHEN THE SWITCH MEANS IS CLOSED. 